Tennis

Kim Clijsters delays tennis comeback because of knee injury

Former world No. 1 Kim Clijsters postponed her comeback attempt Monday due to a knee injury. The 36-year-old has not competed on the WTA Tour since 2012.

Former world No. 1 'determined as ever to get back to the game I love'

Four-time Grand Slam champion Kim Clijsters, who revealed in September she was coming out of retirement, says a knee injury will prevent her from returning to the court in January. (Dan Istitene/Getty Images)

Former world No. 1 Kim Clijsters postponed her comeback attempt Monday due to a knee injury.

The 36-year-old Belgian made the announcement on Twitter.

"I've had to make the decision that I will not be able to compete in January," she posted. "I am undergoing rehab and treatment for a knee injury. It's a setback but I'm determined as ever to get back to the game I love. I really appreciate all your support and encouragement."

Clijsters, who has not competed on the WTA Tour since 2012, revealed in September that she was coming out of retirement.

She won 41 WTA singles titles including four Grand Slam championships, the 2011 Australian Open and three US Open triumphs (2005, 2009, 2010).